Last month there was a power failure at my house. In order to get the car out of the garage, I disconnected the metal bar that connects the garage door to the opener. I did that at the upper end of the bar, where it attaches to the chain drive gizmo. After the power came back on, I connected the bar again. I thought I did it the same as it was connected before. Now, when the electric opener pulls the door open, it does it in a smooth fashion. When it closes the door, however, it shakes in an odd way. I don't think it was doing that before. Can anybody tell me what the problem is? I am including some pictures.

Also, there is a problem with the remote control. It used to work about 30 feet away. Now you have to get within about 10 feet. I suspected that the battery was low, but it still put out 9 volts. Is something going bad in the remote, or is it in the receiver? If it's the receiver, is there a way to repair it without buying a new motor?

Just over from the pin you pulled, there is a hole where a rope should be hanging. If the rope was there you can pull it to releice the trolly and you don't have to take it apart. Check all the hardware for loose nuts, bolts and worn wheels.

Look for witness marks to see if you have reattached the bracket into the correct hole. I don't see any marks in your pics.
And yes, your release rope is missing. It goes into the hole of the cam that has the spring on it.